Field of the Invention
The invention relates to a camera device and a photographing method.
Description of Related Art
People nowadays often unknowingly show signs of strained vision because of reading or watching screens with their eyes, and thus more and more people suffer from ophthalmic diseases. Among the ophthalmic diseases, retinal detachment, macular hemorrhage, or blood vessel hyperplasia may cause irreversible damages to eyes of a patient. Therefore, ocular fundus examinations on retinas, macula lutea, and optic discs located at fundi of eyes always play a decisive role in eye care.
Since the retinas, the macula lutea, and the optic discs are all located at the fundi of the eyes, the ocular fundus examinations are frequently performed by observing the fundi or shooting images of the fundi through pupils of the eyes. However, the size of the pupil of a normal human eye is rather small, and thus it is difficult to obtain the complete look of the fundus in one image-shooting step. When the ocular fundus examination is performed in the real world, paramedics often ask the patient to stare at one fixed point and then slowly change the direction of the stare, such that the paramedics may be allowed to take photographs of the fundus at different angles. Nevertheless, the photographs of the fundus separately taken at different time points may have different levels of exposure, which is not conducive to the subsequent step of stitching images of the fundus. Moreover, in the process of separately taking the photographs of the fundus at different time points, the paramedics and the patient are burdened with the significant time consumed on taking the images of the fundus, and temporary ophthalmodonesis (i.e., trembling motion of the eye) may even occur, such that the shot images of the fundus are blurred. As a result, how to efficiently take wide-field photographs of the fundus as the referential information for clinical diagnosis of ophthalmic diseases is one of the issues to be resolved as soon as possible.